JPS62275302A - Magnetic recording and reproducing device - Google Patents

Abstract

PURPOSE:To simplify the dubbing processing and the editing processing by using an auxiliary rotary magnetic head which traces the slant recording tracks on a magnetic tape in advance of a normal rotary magnetic head. CONSTITUTION:A drum 1 of a rotary magnetic head device 10 contains a pair of auxiliary rotary heads 2A' and 2B' which are set with a 180 deg. angle space and trace the slant recording tracks 2A' and 2B' where the signals preceding at least two fields compared with the slant recording tracks 2A and 2B on a magnetic tape 2 which is traced by a pair of rotary magnetic heads 3A and 3B. Thus it is possible to obtain the reproduction signals preceding at least two fields by the auxiliary rotary magnetic heads in comparison with those reproduction signals obtained by the normal rotary magnetic heads. Then the time delay caused by the recording and reproduction of the PCM signal obtained by a normal magnetic head can be compensated. Therefore the dubbing processing is simplified in a state where the correspondence is secured between the video signal and the PCM signal. Furthermore such editing editing processing is also simplified that the partial data contained in the PCM signal is changed, etc.

Description

Detailed Description of the Invention 3. Detailed Description of the Invention [Industrial Application Field] The present invention provides a recording area for a video signal and a PC on an inclined recording track formed on a magnetic tape by a rotating magnetic head.
The present invention relates to a magnetic recording/reproducing device such as a so-called 8-day video tape recorder (VTR) provided with an M signal recording area.

[Summary of the invention]

The present invention is a 3wss VTR in which a tilted recording track formed on a magnetic tape by a rotating magnetic head is divided, and a video signal is recorded in one recording area, and a PCM signal is recorded in the other recording area. In magnetic recording and reproducing devices such as the above, dubbing and editing processes can be easily performed by providing an auxiliary rotating magnetic node that traces the inclined recording track on the magnetic tape in advance of the regular rotating magnetic head. This is what I did.

[Conventional technology]

Conventionally, a magnetic recording/reproducing device records a video signal in one recording area obtained by dividing an inclined recording track formed on a magnetic tape by a rotating magnetic head, and records a PCM signal in the other recording area. As,
A so-called 8-video tape recorder (VTR) is known.

In this 13 m VTR, as shown in Fig. 5,
Magnetic tapes 52 wound spirally around the circumferential surface of a drum 51 of a rotating magnetic head device in an angular range of 221° were disposed on the drum 51 at angular intervals of 180° while traveling at a constant speed in the direction of arrow X. A pair of rotating magnetic heads 53A, 53B with different azimuth angles are connected to a frame frequency (30Hz).
) by rotating the magnetic tape 52 at a constant speed in the direction of the arrow Y, the bidet No. 13
It is designed to record and play back signals and audio signals.

As shown in FIG. 6, on the magnetic tape 52, an inclined recording track 54 having a length of 221' is traced by the rotating magnetic nodes 53A and 53B during recording.
A and 54B are formed alternately.

In the 8W VTR, as shown in FIG. 7, the audio signal corresponding to the video signal one field before is recorded in the recording area AP of approximately 36 @ section on the trace start side within the above 221°. The color video signal and FM audio signal for one field are recorded in the recording area AV of the subsequent 180' section. In addition, each of the above-mentioned rotating magnetic heads 53A,
Inclined recording track 54A traced by 53B
, 54B, ■ A biloft signal in which four types of frequencies are cyclically switched for each track is used as an ATF (Automatic Track F) signal for tracking control.
(inding) signal together with the audio signal and video signal. At the time of reproduction, as shown in FIG.
B each inclined recording track 54A on the magnetic tape 2;

A playback output is obtained by tracing 54B alternately and sequentially, and tracking control is performed based on the above-mentioned ATF signal.The PCM audio signal is converted into analog after being subjected to time axis expansion processing.

Normally, the PCM audio signal in an 8W VTR is recorded one field behind the recorded video signal in order to perform time axis compression processing etc. in the recording system, and is delayed by one field in order to perform time axis expansion processing etc. in the playback system. It is reproduced l field behind the video signal.

The PCM audio signal handled by the 8■■VTR is a digital audio signal (L, An index word (TD) is added to R) to rearrange the data order, and parity data (Q, P) and an error correction code (CRC) are added to convert the data into serial data for transmission. Error correction processing is now performed using a so-called cross-interleaving technique.

[Problem that the invention seeks to solve]

By the way, as mentioned above, the 8wm V is designed to record a video signal in one recording area into which the inclined recording track formed on the magnetic tape is divided by the rotating magnetic nozzle, and to record a PCM signal in the other recording area. T R
In such magnetic recording and reproducing devices, an error correction code etc. is added to the PCM signal, so if some data in the PCM signal is changed and the error correction code is not also changed, errors will occur during playback. It is no longer possible to perform error correction processing, and it is no longer possible to change or additionally record a part of the recorded data on -i.In addition, when recording and playing back the PCM signal, time axis compression/expansion is required. Since processing and error correction processing are required, there is a time delay for the video signal of one field each during recording and playback, for a total of two fields, and by repeating the dubbing process, the discrepancy between the video and audio can be reduced. There was a problem with the increase.

In view of the above-mentioned conventional problems, the present invention has been developed to perform dubbing processing while ensuring correspondence between a video signal and a PCM signal, and to perform editing processing such as changing some data in a PCM signal. It is an object of the present invention to provide a magnetic recording/reproducing device with a new configuration that allows easy operation.

[Means for solving problems]

In order to achieve the above-mentioned object, the present invention records a video signal in one recording area of a divided inclined recording track formed on a magnetic tape by a rotating magnetic head, and records a PCM signal in the other recording area. In the magnetic recording/reproducing apparatus, the auxiliary rotary magnetic head traces a tilted recording track on which a signal is recorded at least two fields earlier than the tilted recording track on the magnetic tape traced by the regular rotary magnetic head; The present invention is characterized in that it includes a reproduction processing circuit that performs signal processing on the reproduction output from the auxiliary rotary magnetic head.

[Effect]

In the magnetic recording/reproduction 'AH according to the present invention, by obtaining a reproduction signal with the auxiliary rotary magnetic head at least two fields earlier than the reproduction signal produced by the regular rotary magnetic head,
By compensating for the time delay caused by recording and reproducing the PCM signal using the above-mentioned regular rotating magnetic head, the reproduced output video signal and PCM signal are
Ensure correspondence with CM signals.

〔Example〕

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a magnetic recording and reproducing apparatus according to the present invention will be described in detail below with reference to the drawings.

In the embodiment shown in FIGS. 1 to 4, as shown in the block diagram of FIG.
A rotary magnetic head Vtll0 is provided with a magnetic tape 2 spirally wound in an angular range of 180° to the drum 1.
A pair of rotating magnetic heads 38 having mutually different azimuth angles are arranged at an angular interval of .

The present invention is applied to a gm VTR which performs recording and reproduction according to the so-called 8-tsuru format in 3B.

In this embodiment, the magnetic tape 2 is held between a capstan 4 and a pinch roller 5, and the capstan 4 is rotationally driven by a capstan motor 6 at a constant speed in the direction of arrow X in FIG. It is designed to be driven. A capstan motor drive circuit 7 that supplies a drive current to the capstan motor 6 is operated by a capstan servo and drives the capstan motor 6 to rotate at a constant speed in the recording operation mode, and in the playback operation mode, the capstan motor drive circuit 7 supplies a drive current to the capstan motor 6.
Tracking control is performed by changing the rotational speed of the capstan motor 6, that is, the running speed of the magnetic tape 2, in accordance with the ATF error signal supplied from the TF circuit 8.

Further, the drum l of the rotating magnetic head device 10 includes:
As shown in FIG. 2, the pair of rotating magnetic heads 3A,
a pair of auxiliary rotating magnetic nodules 2A', which trace inclined recording tracks 2A', 2B' on which signals of at least two fields earlier are recorded than the inclined recording tracks 2A, 2B on the magnetic tape 2 traced by the magnetic tape 3B; 2B
' are arranged at angular intervals of 180' from each other. The drum 1 is driven by a drum motor (not shown).
It is designed to be rotated at a constant speed in the direction of arrow Y at a frame frequency (30 Hz).

A pair of rotating magnetic heads 3A, 3 disposed on the drum l
B are mode changeover switches 11A and IIB, respectively.
recording amplifiers 12A, 12B and reproducing amplifier 13A via
, 13B.

Further, the pair of auxiliary rotating magnetic nodes 3A' and 3B' are connected to regenerative amplifiers 14A and 14B, respectively. Here, each of the mode changeover switches IIA, 11
B indicates each recording amplifier 12A, IB in the recording operation mode.
Also, in the regenerative operation mode, each regenerative amplifier 1
It is controlled by a system controller (not shown) to select 3A and 13B.

The recording amplifiers 12A and 12B are supplied with recording signals (Ain) and (Bin) from signal adders 15A and 15B, respectively, in the recording operation mode.

The signal adders 15A and 15B are connected to the video input terminal 16.
A video signal (V) in which the video processing system 17 performs signal processing for signal recording on the input video signal (Vin) supplied to , (Ri
Regarding n), the PCM signal (
P) is supplied as a recording signal from the changeover switch 33 through the throat changeover circuit 20, and
ATF pilot signals of four types of frequencies (
f+/fz) and (fz/f4) are selectively supplied, and the ATF pilot signal f+-f is added to the recording signal.
a to the above-mentioned pair of rotating magnetic nodes 3A, 3.
Each recording signal (Ain) and (Bin) to be recorded at B is formed.

Further, each of the regenerative amplifiers 13A and 13B connects the video processing system 17 and the PC via a head switching circuit 23.
It is connected to the M processing system 19.

Further, each of the regenerative amplifiers 13A and 13B is connected to the video processing system 17 via a head switching circuit 23, and the PCM
It is connected to the processing system 19. Furthermore, each of the regenerative amplifiers 13A and 13B is connected to the head switching circuit 23.
is connected to the ATF control circuit 8 via a low pass filter (LPFI) 25 and a changeover switch 26.

Further, each of the regenerative amplifiers 14A and 14B is connected to a band pass filter (BPFz) 28 from a head switching circuit 27.
The head switching circuit 27 is connected to the ATF control circuit 8 via a low-pass filter 30 and the changeover switch 26.

The PCM decoder 29 outputs each reproduction output (A'ou
L) + PCM (No. (P'out) in (B'out)
) to the stereo audio signal (L'out), (R
'out') is reproduced and supplied to the PCM encoder 32 via signal adders 31L and 31R. Each of the signal adders 31L and 31H receives a stereo audio signal (L'ch) + (R'ch) for editing from the editing input terminal 3.
It is supplied from 3L and 33R. Also,
The PCM encoder 32 has an indexnos input terminal 3
Index data (ID') is supplied from 4, and the reproduced stereo audio signal (L'out) + (R
'out) Stereo audio signal for editing above (L
The reproduced audio signal (Ao) obtained by adding and combining the signals 'ch) and (R'ah) is subjected to signal processing such as re-PCM conversion and cross-interleave processing to form a re-recording PCM signal (Po). And the above PCM encoder 3
The re-recording PCM signal (Po) formed in step 2 is supplied from the changeover switch 35 to the signal adders 15A and 15B via the head switching circuit 20.

In the embodiment configured as described above, each hennode switching circuit 20, 23, 27 is connected to one/half of the rotary magnetic hennode device 10.
The switching is performed alternately every 1/2 rotation period, that is, every 1 field period, by means of an RF switching pulse that inverts the scratching characteristics every two rotations.

In the recording operation mode, the recording video signal (V) is input from the video input terminal 16 via the video processing system 17 and the PC is input from each audio input terminal 18L, 18R.
Recording PCM signal (P) input via M processing system 19
are alternately switched every l field by the above-mentioned node switching circuit 20, and each recording signal is obtained by superimposing ATF pilot signals (f+ to r,) of four types of frequencies which are cyclically switched by each signal adder 15A, 15B. (A+n).

(Bin) is supplied to a pair of rotating magnetic nodes 3A and 3B via recording amplifiers 12A and 12B, respectively. The pair of rotating magnetic heads 3A and 3B are 3-IV T
According to the R format, there is a 221° angle on the outer circumference of the drum 1.
The magnetic tape 2 wound spirally is traced diagonally alternately, and an audio signal corresponding to the video signal of one field before is recorded in a recording area (AP) of about 36' on the tracing start side. P which compressed the time axis by converting it into PCM
The CM signal (P) is recorded, and the subsequent 180° recording area (AV) contains one field's worth of video signal (V), FM audio signal, and ATF for tracking control.
Record a video signal with a superimposed signal.

In the playback operation mode, the playback output obtained by sequentially tracing each inclined recording track 2A, 2B on the magnetic tape 2 with the pair of rotating magnetic nozzles 3A, 3B is (Aout), (Bout ) are switched by the head switching circuit 23 to form a reproduced video output signal VPB and a reproduced PCM signal PPB for each field, and output a reproduced video output No. 13 from the video output terminal 40 via the video processing system 17. , the above PC
The M processing system performs reproduction processing such as de-interleaving processing on the reproduced PCM signal PPB and outputs it to the audio output terminal 41.
Playback stereo audio signal (Lout
), (Rout) are output.

Further, in this embodiment, in an editing operation mode in which a portion of a video signal or an audio signal is rewritten on the recorded magnetic tape 2, the pair of rotating magnetic nodes 3A, 3
Inclined recording track 2 on magnetic tape 2 traced by B
The reproduction output (A 'out),
(B'.

ut), a reproduced PCM signal (Po) is formed as shown in FIG. R'out).

Then, & is supplied from the editing input terminals 33L and 33R.
Stereo audio signal (L'ch) for i collection.

(R'out
t) to form a re-recorded audio signal (Ao), and this re-recorded audio signal (Ao) is
The M encoder 32 performs signal processing such as re-PCM conversion and cross-interleave processing using the index data (■D') etc. given from the index input terminal 34 to form a re-recording PCM signal (Po).

In this way, the pair of auxiliary rotating magnetic heads 3A', 3B
' Each playback output (A'out), (B'.

As shown in FIG. 3, the re-recording PCM signal (P'') formed from
'Each playback output (A ou L) + (B
Each reproduced PCM signal and field in (out) is lost once. Therefore, by re-recording the re-recording PCM signal (Po) into each recording area (AP) of the inclined recording tracks 2A and 2B on the magnetic tape 2 using the regular rotary magnetic heads 3A and 3B, the PCM A part of the data can be changed or additionally recorded on a PCM audio signal without disturbing the correspondence relationship between the audio signal and the video signal.

Here, in the editing operation mode, each reproduction output (A
'ouL), (B'ouL) pilot signal (A
Switch 2 to change TF from low pass filter 30
6 to the ATF control circuit 8 for tracking control. In this way, by controlling the changeover switch 26 in the editing operation mode, for example, as shown with diagonal lines in FIG. When performing so-called insert editing in which each recording area (AV) of the inclined recording tracks 2A and 2B on the magnetic tape 2 is erased and rewritten with a new video signal using the regular rotating magnetic heads 3A and 3B. Also, to the above pair of auxiliary rotating magnets・Grot 3
Each playback output (A'out), (B
Tracking control can be performed correctly based on the pilot signal (ATF) in 'out'.

In addition, in the above-mentioned embodiment, the present invention was applied to an 8 mm VTR.
However, the present invention is not limited to the above-described embodiments, but can also be applied to a so-called dubbing device that forms a reproduction tape using two magnetic recording and reproducing devices. It can be passed.

〔Effect of the invention〕

As is clear from the description of the embodiments described above, in the magnetic recording and reproducing apparatus according to the present invention, the above-mentioned reproduction signal is obtained by using the auxiliary rotary magnetic head to obtain a reproduced signal that is at least two fields earlier than the reproduced signal by the regular rotary magnetic head. Compensate for the time delay caused by recording and reproducing PCM signals using a regular rotating magnetic head, perform dubbing processing while ensuring correspondence between the video signal and PCM signal, or change some data in the PCM signal. Editing processing can be performed easily.

[Brief explanation of drawings]

FIG. 1 is a block diagram showing an embodiment in which the present invention is applied to a 13 In VTR, FIG. 2 is a schematic diagram showing the trace state of each rotating magnetic head in the above embodiment, and FIG. 4 is a timing chart for explaining the PCM signal rewriting operation in the above embodiment, and FIG. 4 is a schematic diagram for explaining the insert editing processing operation of the video issue in the above embodiment. FIG. 5 is a schematic diagram showing the configuration of a rotary magnetic head device in a general 13VTR, and FIG.
FIG. 7 is a schematic diagram showing a recording track pattern of a VTR, FIG. 7 is a timing chart showing a recording operation of an 8 mm VTR, and FIG. 8 is a timing chart showing a reproducing operation. l...Drum 2...Magnetic tape 3A, 3B,
3A', 3B'...Rotating magnetic head 4...Capstan 6...Capstan motor
7... Capstan motor drive circuit
8... ATF control circuit 10... Rotating magnetic head devices 11A, 11B... Mode changeover switch 15A,
15B...Signal adder 17...Video processing system 19...PCM processing system 20.23.27...Head switching circuit 21...
Pilot signal generator 25.30...Low pass filter 26.33...Switch 29...P, CM decoder 31L, 31R...Signal adder 32...PCM encoder

Claims (1)

[Claims] Magnetic recording and reproducing in which a tilted recording track formed on a magnetic tape by a rotating magnetic head is divided, and a video signal is recorded in one recording area, and a PCM signal is recorded in the other recording area. In the apparatus, an auxiliary rotary magnetic head that traces a tilted recording track on which a signal is recorded at least two fields earlier than the tilted recording track on the magnetic tape traced by the regular rotary magnetic head; 1. A magnetic recording and reproducing device comprising a reproduction processing circuit that performs signal processing on reproduction output.